Android - 视图点击效果

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@android:color/transparent"
android:state_pressed="true"/>
<item android:drawable="@android:color/transparent"
android:state_enabled="false"/>
<item android:drawable="@color/white"/>
</selector>

android:background="?android:attr/selectableItemBackground"

<selector xmlns:android="http://schemas.android.com/apk/res/android"
android:exitFadeDuration="@android:integer/config_mediumAnimTime">

<item android:drawable="@color/transparent"
android:state_window_focused="false"/>

<!-- Even though these two point to the same resource, have two states so the drawable will invalidate itself when coming out of pressed state. -->
<item android:drawable="@drawable/list_selector_background_disabled"
android:state_enabled="false"
android:state_focused="true"
android:state_pressed="true"/>
<item android:drawable="@drawable/list_selector_background_disabled"
android:state_enabled="false"
android:state_focused="true"/>
<item android:drawable="@drawable/list_selector_background_transition"
android:state_focused="true"
android:state_pressed="true"/>
<item android:drawable="@drawable/list_selector_background_transition"
android:state_focused="false"
android:state_pressed="true"/>
<item android:drawable="@drawable/list_selector_background_focused"
android:state_focused="true"/>
<item android:drawable="@color/transparent"/>

</selector>